Optimal conditions for the production of exopolysaccharide by marine microorganism Hahella chejuensis

Abstract

A marine microorganism, strain 96CJ10356 produced exopolysaccharide, designated as EPS-R. To optimize culture conditions for the production of EPS-R, carbon and nitrogen sources, mineral salts, temperature, and pH were examined. From this study, STN medium for the production of EPS-R was suggested as follows; sucrose 20 g, tryptone 10 g, NaCl 10 g, MgSO4 5 g, CaCl 2 1 g, KH2PO4 76 mg, K2HPO 4 83 mg, FeCl2 5 mg, MnCl, 1 mg, NaMoO4 1 mg, and ZnCl2 1 mg per liter at pH 7.0. About 9.23 g/L of EPS-R was obtained from STN medium after cultivation for 120 h at 25°C in a 5-liter jar fermentor with an aeration rate of 0.17 vvm. Apparent viscosity and flocculation activity of the culture broth were increased with the production of EPS-R and the maximal values were 415 cP and 1400 unit/mL against 0.5% activated carbon, respectively.